The present invention relates generally to a pivoting handle assembly having weight compensation. More particularly, the present invention relates to a pivoting handle assembly having weight compensation which aids an operator by supporting the weight of the pivoting handle assembly having weight compensation, thereby reducing operator fatigue.
In many manufacturing and assembly operations, it is necessary for operators to support and maneuver relatively large and/or heavy handles which are part of material handling devices. For example, in motor vehicle assembly, it is often beneficial to have long handles on material handling devices used to, for example, assemble motor vehicle doors on motor vehicle frames. Such motor vehicle doors are relatively large and heavy. The long handles enable an operator to position the motor vehicle doors in a wider range of elevations without over-extending the operator. However, the long handles become heavy and burden the operator. This is particularly the case when operators work eight (8) hour shifts, or longer, for five (5), or more, days a week. Over time, operators often develop fatigue which can have a negative impact on productivity and, in many cases, operators develop back problems and/or other physical injuries and health problems as a result of supporting, transporting and/or positioning such relatively large and/or heavy handles. Such physical injuries and health problems result in work days being missed by the operators, greater than desired medical costs and decreased operator morale.
Several prior art handles have been used to assist operators in supporting, transporting and/or positioning relatively large and/or heavy parts in manufacturing and assembly operations. However, a limitation of many known prior art handles is that they are heavy. In many situations, such as assembling motor vehicle doors onto a motor vehicle frame, it is necessary to position and support the part to be assembled in rather precise alignment with other parts to obtain a high quality end product. Many prior art handles are awkward for the operator to support and hinder the operator's ability to consistently carry out manufacturing and assembly operations where relatively precise alignment is necessary and/or desired.
Accordingly, an object of the present invention is the provision of a pivoting handle assembly having weight compensation which reduces the apparent weight of the pivoting handle assembly to an operator.
Another object of the present invention is to provide a pivoting handle assembly having weight compensation which is economical to fabricate, maintain and use.
Yet another object of the present invention is to provide a pivoting handle assembly having weight compensation which aids operators in supporting, transporting and/or positioning parts, part handling fixtures and other materials during manufacturing and assembly operations.
These and other objects of the present invention are attained by the provision of a pivoting handle assembly having weight compensation which is anticipated to be used in conjunction with parts, part handling fixtures and other materials to reduce the apparent weight of the pivoting handle assembly having weight compensation to an operator and thereby reduce operator fatigue. In particular, an elongated spring member is positioned in the interior of an elongated pivoting arm member to at least partially compensate for the weight of the pivoting handle assembly having weight compensation that an operator must hold. A pin extends through the elongated spring member and has an internally threaded nut attached to one end thereof and is secured at the other end to one end of a chain by a master link. The chain is secured at its other end to a stationary arm member by a second master link. The elongated spring member is contained between two (2) screws on one end and the internally threaded nut on the other end. As elongated pivoting arm member is rotated in a first rotational direction, the chain is wrapped around the center diameter of a pivot portion of the stationary arm member and the pin is pulled to compensate for the change in length, thus compressing the elongated spring member. When the elongated spring member is compressed, it imposes a torque about the center diameter of the pivot portion of the stationary arm member. This applied torque tends to rotate the stationary arm member in a second rotational direction opposite to the first rotational direction and thereby reduces the apparent weight of the pivoting handle assembly to the operator. The internally threaded nut is preferably adjustable to compensate for varying weights of the pivoting handle assemblies having weight compensation, as well as for operator preferences, and a relatively long spring is preferably utilized to assist in maintaining the spring rate relatively constant over a wide range of positions.
Other advantages and novel features of the present invention will become apparent in the following detailed description of the invention when considered in conjunction with the accompanying drawings.